Abstract
We had recently demonstrated a room temperature operated widely tunable THz-wave generation (frequency : 0.9-2.1 THz, wavelength : 140-310 μm) introducing a Si prism coupler onto a LiNbO3 crystal which was pumped by a Q-switched Nd:YAG laser. The process involved is an optical parametric oscillation (OPO) utilizing the polariton mode scattering of LiNbO3. This tunable THz-wave source was applied to the problem of differential imaging. In a proof-of-concept experiment, we optically tagged objects embedded in a shade and measured the difference between transmittance at two wavelengths. The image of a tagged object was emphasized in comparison with that of an untagged objects. Differential THz imaging has not been reported previously, to our knowledge, mainly because of the lack of convenient tunable THz-wave sources. It seems possible to use dual-wavelength differential transmittance spectroscopy in the THz-wave region to monitor the gases in the industry.
| Original language | English |
|---|---|
| Pages (from-to) | 20-26 |
| Number of pages | 7 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 3465 |
| Publication status | Published - 1998 Dec 1 |
| Event | Proceedings of the 1998 Conference on Millimeter and Submillimeter Waves IV - San Diego, CA, USA Duration: 1998 Jul 20 → 1998 Jul 23 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering